package 工具包static;

import java.util.Random;

public class useToCreateYZM {
    //一班工具包不用创建对象所以变成私有制
    private useToCreateYZM(){}
    public static String createYZM(int n){
        String code="";
        String N="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ123456789";
        Random sj=new Random();
        for (int i=0;i<n;i++){
            code+=N.charAt(sj.nextInt(61));
        }
        return code;
    }
}
